Dont disregard the chat on the left side.....sometimes people give the location of certain players(usually snipers) which they are unable to spot using the spotted button(possibly becuz they are in a heli or plane)

YOu can also place claymores in the brush around areas where soldiers run by often on maps like Myanmar. If there is cover nearby some brush then place claymores in the brush and an opfor with half-health runs into your claymore as they're headed for cover. Easy kill, fun trap.

Burst fire at long range to reduce overall recoil.
A good recon factors in bullet drop(altough not all sniper rifles have the same bullet drop) before taking the shot.
A good engineer knows when to fire a rocket, and when to let the enemy armor pass.
Sometimes, its better to fire an RPG in the general direction of a vehicle, THEN tag it with your dart.
Play the objective; cap flags- don't run around like a maniac shooting anything that moves.
Know your maps- flanking routes, secret corridors, roofs, hidding spots, rooms-anything to get the upper hand on your opponent.
Don't open your parachute to early(or to late!), you might end up getting shot down, or you might turn into a pancake.
Take a break every few games- give your eyes a rest(you need to SEE the enemy to kill them-you can't play games blind!)
Reatreat if you are outgunned- its better to live and fight again then to die in a hopeless battle.
Have fun! OH! and dont forget to blow stuff up!

Don't be total noobs - don't use shotguns or airburst grenade launchers.
(How's that?)
(Better gimme ur money and I'll get a nice laptop and BF3 and you'll never see me again neither on forum nor battlefield )